This invention is directed to an apparatus for ultrasonically disintegrating and aspirating tissue in a surgical operation. More particularly, this invention relates to an improved and novel surgical apparatus for disintegrating and aspirating a wide range of body tissues. Use of ultrasonically vibrated surgical tools to remove various types of body tissues is well known in the art. Certain of these instruments are being commonly used in various surgical procedures such as in the removal of cataracts from the eye as illustrated by U.S. Pat. No. 3,589,363 issued June 29, 1971 to A. Banko and C. P. Kelman. Other specialized ultrasonically driven surgical instruments have been patented, though the extent of actual use and practice is unknown. However, except for the ultrasonically driven dental prophylaxis unit (which is a widely accepted and successful instrument for cleaning the teeth professionally) and the use of ultrasonic instruments to surgically remove cataracts, the use of ultrasonically vibrated tools in the surgical removal of body tissues is not a common and accepted prodedure at present.
Several patents and patent applications are known which describe the use of such ultrasonically vibrated tools to remove tissues among which are U.S. patent application Ser. No. 555,474 filed Mar. 5, 1975 and assigned to the assignee of the present application, U.S. Pat. No. 3,526,219 issued Sept. 1, 1970, to L. Balamuth, and U.S. Pat. No. 3,565,062 issued Feb. 23, 1971 to A. Kuris. While the aforementioned patents describe various types of instrumentation for removing tissue, bodily tissues exhibit a wide range of mechanical characteristics; i.e., compliance, ranging from liquid to a relatively hard and brittle material such as bone. It is therefore unrealistic to assume that a single type of instrument can satisfactorily be used on all of the different types of tissue. We have found that while the apparatus and method described in the reference U.S. Patent Application is satisfactory for certain low-elasticity neurological tumorous tissue it is not satisfactory when employed on more elastic compliant tissue. Similarly it has been found that the instrumentation utilized in performing the cataract removal in accordance with the aforementioned U.S. Pat. No. 3,589,363 is quite unsuitable for removing neurological tumors and similar tissue. In regard to the instrumentation described in U.S. Pat. No. 3,526,219, it is difficult to ascertain the effectiveness of such instrumentation due to the broad nature of the teaching.